Streptococcus mutans plays a pivotal role in the development of caries. The bacterium converts fermentable sugars into organic acids and thus generates an acidic microenvironment. The organic acids are capable of demineralizing the dental enamel and thus bring about, or promote, the cariotic lesions. Moreover, S. mutans generates a non-water-soluble glucan matrix. This glucan matrix supports the development and adhesion of plaque and the adhesion of S. mutans at the surface of the teeth. Furthermore, it has been shown that other bacteria, too, are frequently found in carotic lesions, but always together with S. mutans. Accordingly, S. mutans is currently considered to be necessary for the development of cariotic lesions.
There is a constant need for remedies with which the development of cariotic lesions can be prevented. In this context, the invention intends to indicate remedies with which it is possible to act on S. mutans in order to avoid, stop or slow down the development of cariotic lesions. The invention also intends to indicate preparation methods for such remedies.
In the past, an entire series of remedies have been tested for controlling cariotic lesions, in particular in order to avoid or at least delay the appearance thereof. A person skilled in the art is familiar in particular with traditional chemical remedies for controlling caries and caries-associated microorganisms, as they are used in toothpastes and/or mouthwashes and/or other dental care products. In addition, however, it has also been attempted to control caries-associated microorganisms by means of other microorganisms or their products, in particular it has been attempted to reduce their amounts on teeth or in the oral cavity, or otherwise to influence the cariogenicity. Such an approach is described for example in WO 2005/027265 A1. However, the disadvantage is that the use of live microorganisms in oral care products is frequently disliked by consumers or entirely banned by legislators. Moreover, live microorganisms may influence the taste and/or the appearance of a product containing them as the result of metabolites; this influence may not be desired for every product for controlling cariotic lesions. Furthermore, the use of live organisms in products designed for controlling cariotic lesions limits the shelf-life of said products.
It is therefore quite generally attempted in various technical fields to use metabolically inactive microorganisms, in particular lyophilized microorganisms, instead of live microorganisms. The problem here, however, is that such microorganisms may, under conditions which are suitable for them, return to the metabolically active state, for example when they get into an aqueous medium which suits them. Accordingly, the use of metabolically inactive microorganisms entails serious limitations of the possible composition of a product containing them.
It has therefore been attempted in quite different technical fields to prepare products with destroyed microorganisms instead of live or metabolically active microorganisms. Thus, for example, WO 01/95741 A1 shows a foodstuff for promoting the intestinal balance, the food product containing nonviable Lactobacilli. The Lactobacilli can be made nonviable by means of heat treatment, for example by means of pasteurization or sterilization. Said document, however, also mentions the risk of losing, as a result of the heat treatment, some health-promoting effects of microorganisms which can otherwise be achieved. While the document says that these health-promoting effects can be eliminated “selectively”, the document does, in fact, not teach anything about how the loss of a desired health-promoting feature might be avoided during the heat treatment of microorganisms. In the light of said document, therefore, a person skilled in the art can neither predict nor speculate in a meaningful manner as to which health-promoting effects are lost as a result of a heat treatment of microorganisms and which are not. In particular, it cannot be predicted or estimated whether an anticariogenic effect is lost as a result of heat treatment.
It is therefore the object of the present invention to indicate remedies for controlling cariotic lesions, in particular remedies for avoiding or delaying the development of cariotic lesions. In particular, it is intended that the remedies are guaranteed to bring about the desired effect. It is intended that their preparation be simple and inexpensive and that, if possible, the above-described disadvantages be avoided or reduced to a minor extent.